Gas turbine engines used in aircraft often include a fan assembly that is driven by an engine core to push air through the engine and provide thrust for the aircraft. A typical fan assembly includes a fan rotor having blades and a fan case that extends around the blades of the fan rotor. During operation, the fan blades of the fan rotor are rotated to push air through the engine. The fan case both guides the air pushed by the fan blades and provides a protective band that blocks fan blades from being thrown out of the fan assembly in case of a blade-off event in which a fan blade is released from the fan rotor.
Fan cases sometimes include metallic shrouds and liners positioned between the metallic shroud and the fan blades. Liners are generally used to achieve a desired dimensional tolerance between the fan blades and the fan case. The distance between the fan blades and the fan case may vary due to variations in dimensional tolerances or thermo-mechanical deflections. As such, liners may include an abraidable layer that the fan blades may contact without damaging the shroud. Liners may be coupled to metallic shrouds by hanger features that extend from the metallic shrouds or by adhesives that provide a permanent bond to the metallic shrouds. Over time, the liners may need to be repaired or replaced.